Shingle



Aug. 19, 1930. D EE 1,773,352

SHINGLE Original Filed llay 11, 1926 N VE N TOE 32 002/51? F/M EV Patented Aug. 19, 1930 UNITED- STATES PATENT orrice DOZIER FINLEY, F BERKELEY, CALIFORNIA, ASSIGNOR TO THE PARAFFINE COM- PANIES, INC., OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF DELAWARE SHINGLE Original application filed May 11,1926, Serial No.-108,241. Divided and 'this application filed Maya, 1927. 1 Serial No. 188,129.

My invention relates to shingles and especially to shingles cut without-waste from a parent sheet of prepared roofing.

This application is a division of my copending application for Letters Patent of the United States, Serial Number 108,241, filed May 11, 1926.

The principal object of the invention is the provision of a shingle such that a given roof surface may be covered with a smaller amount of roofing material than has heretofore been possible.

Another object of the invention is to produce in a single cutting operation two variant forms of a single type of shingle, such that the. two forms, tho of different shape, may be used together and interchangeably, and also independently.

Another object of the invention is the cutting of shingles in such a manner that direct wastage of one portion of the parent sheet fixes upon another phase of the cutting operation a condition by which another portion a of the parent sheet, larger than the wasted portion, is usefully conserved. I t 1 Another object is to produce at a-single cutting operation two shingles of the same type and of equal exposure, in which difierent quantities of the parent material are used,

whereby two different pecuniary values arev automatically made to attach to things of the same ultimate superficial appearance.-

My invention possesses other objects and features of advantage some of which with the foregoing will be set forth in the following description of my invention which is illustrated in the drawings forming part of the specification. It isto be understood that I do not limit-myself to the showing made by the said description and drawings as I may adopt variant forms of my invention within the scope of the claim.

Referring to the drawings: Figures 1 and 2 are, respectively, plan views of the unlike shingle units embodying my invention.

Figure 3 is a plan view of a-portion of a parent sheet, showin the shingle units in the cuttingposition and efore the separation of the umts. v

Figuret is a plan view of a portion of a roof formedwith my shingle, showing the interchangeablity of the two forms.

Figure 5 is a plan view of a modified form I of the shingle unit shown in Figure 1. In the manufacture of shinglesfrom a parent sheet of prepared roofing, it is obvious that wastage of material is a vital factor in the design. It is also obvious that thereis a very high value in any method 'of cutting and generally speaking having inclined portions crossing the axial line at about degrees thereto and having parallel portions alternating with the inclined portions and of.

approximately equal length.

Shingles formed in this manner can be laid by lapping one over the other in such a manner that a projecting tongue formed by the zigzag cut on the overlying shingle will match with a recess of the under shingle. If the dimensions are properly chosen, it will be found that a series of such shingles laid in this manner will not only cover an area completely but that there will be a lap at every point sufiicient to prevent falling rain from reaching the underlying structure, providing of course that there is a cooperating slope to assist in the rapid carrying off of the water. 1

It will be found however that the amount those parts .of the lap which materially exceed the minimum. Material thus needlessly used should be constructively diverted to the useful purpose of weather exposure or the equally essential purpose of use in the necessary laps which go with each exposed portion.

In order to make use of the parent sheet of material most economically, it has been found that where four or a higher even number of shingle strips are cut transversely of the sheet, it is possible to notch what will be the upper, or nominally straight edge of the shingles. The notches on the pair of shingle strips cut from the center of the parent sheet my method of cutting, increases as the num ber of such strips increases. -It is understood that the number-of shingles measured transversely of the parent sheet will always be even.

A mathematical expression for calculating the dimensions, area and cutting constants of any particular type of shingle involving this principle follows a=number of shingle strips which will have an aggregate area of 100 square feet of surface exposed to the weather when laid. b=w idih of the parent sheet in inches. c=1ength of each shingle stripin inches. d=-number cf shingle strips in a single section of the parent sheet taken transversely (always an even num e e==depth of notches in the,uotched upper edge of the strip, in inches.

[ lap at upper edge ot hexagon when laid (least lap) in inches.

. exposed area of each shingle strip in square feet, or J T exposed area in square inches. 14400 effective exposed width (average width) of I each shingle strip exposed to weather.

Since the shingle strips arcomplementary, the area exposed by the notch of an overlying shingle is equal in area and similar in shape to the area covered by the tab; therefore the extreme width of the shingle is twice the average exposed width plus the overlap, or;

28800 extreme width of asingle shingle strip.

A portion of the parent strip corresponding in Width to the average Width of one shingle strip is occupied jointly by two such strips, and hence when two transverse shingle strips gle strips will have an extreme width of are formed from the parentlstrip, the quan- 144.00

therefore a pair of interlocked ((2 2) shin is multiplied by 3d and not 2d;

2160003 (1) i 2f= b but Where d is 4 then Where 0? is greater'than 4 v The general formula (3) satisfies the conditions of the specific cases in 1) and (2).

It will be noted that. the broken line form of the cut which forms the shingle tabs is not material to this formula as the only factors of the formula concerning the shingle tabs are the number of shingles required to cover one square and the length of each individual shingle, which two factors automatically determine the average Width exposed. Beyond that, any number or shape of tabs can be chosen so long'as they can be cut in matched relation. The same applies to the notches at the top of the shinglel There is a factor in the formula, however,

which does not appear in the above state ment, and this concerns the shape of the tabs and the notches at the top. If e is considerably greater than f or, in some cases, if it is only nearly as great as f it will be found that the distancefrom some one (the nearest) portion of the exposed surface of an underlying shingle to the edge of some one (the nearest) part of the notched portion of the top edge of the same shingle is less than fin which event the calculation must either be repeated, assigning a smaller value to e or a greater value to f, orelse it may be found only necessary to make a few minor changes in the dimensioning and placing of the diagonal lines which form the end portion of the notches and the sides of the hexagon which are inclined to the longitudinal axis.

It will be appreciated that as (1 becomes larger in value, the economy of cutting shingle strips according to this procedure becomes more pronounced.

My shingle may be cut on any suitable shingle cutting machine, but it is contemplated that these shingles will be cut on a machine which forms the subject matter of a co-pending application Serial Number 627,496. It Will also be understood that I may, or may not, notch the shingles cut from the outer strip, of the parent sheet,

alongtheir nominally straight upperedges.

That is, I may cut all of the parent material into shingle units similar to that shown in Figure 1. Thus if four shingle strips are made across the arent sheet, the form of I shingle shownin igure 1, can be produced in any amountfromto 100 percent of the parent sheet, and the other form shown in Figure 2 may be produced in any amount from 0 to 50 percent of the total.

In Figure 3 of the drawings, I have shown the proportions of typical shingle units, embodying my invention. In this example the shingles are cut from aparent sheet of roofing material, in which values may be assigned as follows:

With the dimensions indicated it will be found that 84 shingles can be cutfrom 181 square feet ofparent material. -This will be sufiicient to cover one square with an average effective exposure of each shingle of about 5", and a minimum lap of about 2" Where the shingles are cut in such proportions that those of the form shown in Figure 1 are produced in numbers equal to those shown in Figure 2, only'172.4 square feet of material will have beenused in cutting 84 of the Figure 1 form; and 189.6 square "feet of'the parent sheet will have been used in cutting 84,0f the Figure 2 form. From this it appears that 17.2 s uare feet more of material is employed in t e Figure 2 variation than in the Figure 1 variation,

per square of finished roofing. If equal quantities of the forms shown in Figures 1 and 2, are out from the parentstrip, the gross saving of material is represented by the difference between 181 square feet and 189.6 square feet, that is, a saving of 8.6 square feet 0f parent material to each square of roofing.

That the economies thus efi'ected are very real, and may be reflected in materially lower selling costs of the product, needs no argu-- ment. A further economy lies in the fact that in the shingle shown in Figure 1 there is 9% less material by weight, than in the shingle shown in Figure 2, and this represents an additional economy and, advantage in the matter of freight charges, especially when shipments are made for a considerable distance. I v. I Referring particularly to Figure 3, the

1 parent sheet of roofing material is separated into four longitudinally extending shingle strips by cuts defined by the zigzag lines 6,

I 7 and 8. With the parent sheet divided into four shingle strips, there will be three such zigzag lines, and each will be 'reversely svmmetrical about a longitudinally extending axis. The zigzag line 6 is reversely symmet- V rical about the axis 9; the zigzag line 7 is reversely symmetrical about the axis 11; and the zigzag line 8 is reversely symmetrical about the axis 12. It will be noted that the central or inner axis 11, extends down the center of the parent sheet, and that the axes 9 and 12 are evenly spaced on each side of comprises a substantially straight line as indicated in Figure 2. If all of the shingles to be cut from the parent sheet are to be formed as shown in Figure 1, notches 14,

defined by the broken line 16 are formed in the outer edges and it will be noted that the boundary edge thus formed comprises a broken linereversely symmetrical about the longitudinally extending "axis 17; that this broken line is'identical with the broken line- 7 and that the axis 17 is spaced the same distancefrom the axis 9, that the latter is from the central axis 11. I

It will also be noted that the central zigzag line 7 is comprise-d of parallel portions 21 and 22connected by transversely extending portions 23 and 2t; and that the zigzag lines 6 and 8 are of the same character, 'differing only in the length of the parallel and the transverse portions.

From the above it'will be understood that the parent sheet is divided into an even number of shingle strips, which in the cutting position dovetail together ;or are complementary to each other along contiguous edges. It will also be seen that all of these strips may be' identical or that there may be like pairs of unlike strips, butin all cases there s one edge, the exposed edge when the shingle is laid and defined bythe lines 6 and 8, which 18 identical in all units. Also in all cases the contiguous edges of the inner shingle strips defined by lin 7 and which are the normally unexposed edges when the shingle strips are laid, are interlocked.

At intervals the'shingle strips'are severed into the separate units by transversely extending cuts defined by the lines 28, which, as to any one group of shingles extending across the parent sheet are staggered. Preferably these transverse cuts are perpendicular to the longitudinal axis of the sheet but this is not necessarily so; and in Figure 5 a different relationship is shown.

In Figure 4 is shown a section of roof laid. with my shinglesand showing both variant forms,notched back as" shown in Figurel,

and straight back as shown in Figure 2, laid interchangeably. While circumstances would ordinarily prevent the mixing up of the two forms of shingles in this manner, it

might happen; and so far as usefulness and suitability are concerned, the two forms of shingles are entirelyinterchangeable, it be- .4- a I I 1,773,352

are laid irrespective of the type of shingle F v used.

In- Figure I- have shown a variant form of the shingle illustrated in Figure 1. This 5 shingle difi'ers' from the type shown in Figure 1, chiefly by its rounded corners, the parallel portions 31 and 32 of the weather exposed edge mer'ginginto the transverse portions 33 and 34 in the curves 36. The boundary m edges of this shingle are thus formed of broken lines in which the corners are smoothed into curves.

This form of shingle has some advantages 1 because the rounded corners result'in a slight- 1y increased lap at the corner. Consequent- 1y the notching of the back edge may be made deeper to bring this lap back to the minimum amount, thus securing an additional economy of material.

6; I claim:

A strip shingle having exposed comp1e-' mentary semi-hexagonal tabs and recesses along its weather-exposed edge and unex posed complementary semi-hexagonal tabs and recesses alongits unexposed edge, the unexposed tabs being opposite the exposed tabs and having less height than the exposed tabs.

In testimony whereof, I have hereuntoset 'my hand. DOZIER FINLEY. 

